39958 has 4 divisors (see below), whose sum is σ = 59940. Its totient is φ = 19978.

The previous prime is 39953. The next prime is 39971. The reversal of 39958 is 85993.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 85993 = 113 ⋅761.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39953) by changing a digit.

39958 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9988 + ... + 9991.

It is an arithmetic number, because the mean of its divisors is an integer number (14985).

2³⁹⁹⁵⁸ is an apocalyptic number.

39958 is a deficient number, since it is larger than the sum of its proper divisors (19982).

39958 is a wasteful number, since it uses less digits than its factorization.

39958 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19981.

The product of its digits is 9720, while the sum is 34.

The square root of 39958 is about 199.8949724230. The cubic root of 39958 is about 34.1875449100.

The spelling of 39958 in words is "thirty-nine thousand, nine hundred fifty-eight".